Climate Change Impacts on Bumblebee Species

Climate change poses a multifaceted threat to bumblebee populations worldwide by altering temperature regimes, disrupting phenology and fragmenting suitable habitat. Rising mean temperatures and more frequent heatwaves push individual foragers and colonies toward physiological limits, reducing foraging efficiency and brood development. Concurrent shifts in seasonal patterns can desynchronise floral resource availability and bee emergence, undermining pollination services. Range-shift modelling predicts contractions in core habitats for many species, particularly at lower latitudes and along elevational gradients, while isolated thermal refugia may emerge where dispersal permits. At the colony level, thermal stress interacts with nutritional and hydric demands, with smaller or nutritionally compromised colonies proving especially vulnerable. Molecular studies reveal that gene expression responses to cold stress vary regionally, whereas heat-stress responses are constrained, implying limited adaptive capacity to warming. Collectively, these findings underscore the urgent need for targeted landscape management, the preservation of climatic refuges and strategies that bolster colony resilience through diverse, high-quality floral resources.

Research from Nature Portfolio

A species-specific assessment of future distributions under multiple climate scenarios has revealed significant range losses even under moderate warming, with dispersal rates unlikely to keep pace with shifting climatic envelopes. Hotspot areas where several species may persist or expand have been identified, guiding priority conservation zones. Physiological assessments across latitudinal and altitudinal populations of a widespread bumblebee demonstrated strong local adaptation in cold tolerance but invariant upper thermal limits. Genome-wide transcriptional profiling linked distinct gene-expression modules to cold tolerance, whereas the uniformity of heat-stress responses suggests constrained adaptive potential to rising temperatures.

Climate Change Impacts on Bumblebee Species publication trend

The graph below shows the total number of articles in climate change impacts on bumblebee species across all publications each year (not limited to Nature Index journals).

Technical terms

CTmax: The critical thermal maximum, or highest temperature at which bumblebees maintain coordinated activity before physiological failure.

Warming Tolerance: The difference between a bee’s CTmax and the maximum habitat temperature, indicating vulnerability to further warming.

Thermal Performance Curve (TPC): A graphical representation of physiological or behavioural performance across a temperature gradient, showing optimal and lethal thresholds.

Dispersal Capacity: The inherent ability of a species to move across the landscape and colonise new suitable habitats in response to climatic changes.

Occupancy Model: A statistical framework that estimates species presence while accounting for imperfect detection, used to infer changes in site occupancy over time.

References

1. The heat is on: reduced detection of floral scents after heatwaves in bumblebees. Proceedings of the Royal Society B (2024).
2. Thermodynamics, thermal performance and climate change: temperature regimes for bumblebee (Bombus spp.) colonies as examples of superorganisms. Frontiers in Bee Science (2024).
3. Biogeographic parallels in thermal tolerance and gene expression variation under temperature stress in a widespread bumble bee. Scientific Reports (2020).
4. Climate change-driven range losses among bumblebee species are poised to accelerate. Scientific Reports (2018).
5. Climate change winners and losers among North American bumblebees. Biology Letters (2022).